With hostilities flaring in Iraq, the U.S.-led authority wants to tighten controls over the surging number of private armed security teams being hired to protect U.S. government agencies and contractors involved in rebuilding.

With an estimated 20,000 private security workers on the ground, the Coalition Provisional Authority is increasingly concerned about the quality of the security teams, the weapons they use and the rules that will govern them after June 30, when the authority transfers political power to an interim Iraqi government.

"It's an important issue that needs to be addressed, and that's what we're doing," said Bryan Whitman, a Pentagon spokesman.

A draft CPA document on vetting and registering the security firms said many "are already operating in Iraq without the benefit of appropriate registration and authorization of the Ministry of Interior." "Appropriate mechanisms must be put into place" to register them, the draft said.

The draft plan would require security companies to list all employees working in Iraq, and to provide copies of the contracts under which they are working and the serial numbers of their weapons. If the company sought to increase its weapons cache after its initial registration, it would have to coordinate with the Ministry of Interior, the draft states. Weapons could be carried by employees only while "on duty" and would be stored in an armory or "secure facility" otherwise.

"Due consideration will be given to the need to vet companies, their directors and employees in order to ensure that criminal elements are identified and to avoid situations such as militias trying to legitimize themselves," according to the draft.

Many operational details are spelled out only in the contracts between security firms and the companies and government agencies that hire them, according to several private security firms.

The CPA now restricts the weapons private security teams may use to small arms with ammunition as large as 7.62mm and to some other defensive weapons. A Dec. 31 coalition rule spells out circumstances under which security firms can use deadly force, including self-defense, the defense of people or property specified in their contracts, and the defense of civilians.

Coalition contractors and their employees currently are subject to the legal jurisdiction of their parent countries because there is no Iraqi legal system, a CPA order states.

But with the June 30 handover, that condition "becomes a major issue," and "there is not a lot of clarity yet" on what laws will govern security firms, said Mike Baker, chief executive of D.C.-based Diligence LLC, which provides security for both government and private operations in Iraq.

Attempts to coordinate operations between private security firms and the military -- and operations among the companies themselves -- have been underway for months. But that pace has quickened.

The CPA's program management office is reviewing bids on a master contract to coordinate security among the 10 largest prime contractors and their subcontractors working on $18.4 billion in U.S.-backed reconstruction as they deploy throughout Iraq. In the meantime, the program management office is "trying to get at least some level of intelligence sanitized from the military that could be given to contractors," said Capt. Bruce A. Cole, spokesman for the program management office in Baghdad.

As violence increased in the last two weeks, private security firms learned that they could not rely on U.S. or coalition forces to rescue them under attack. The companies have begun to band together to share information and to coordinate their own rescue teams for life-threatening situations.

Col. Jill Morgenthaler, a spokeswoman for the U.S. military in Baghdad, said "the military cannot guarantee the safety of civilians" in Iraq. "When we can, we respond."

Military operations against insurgents take precedence, although commanders can decide to rescue civilians depending "on mission, situation, conditions," Morgenthaler said by e-mail.

One CPA official said the unexpected central role played by contractors in Iraq has forced the U.S. government to pay more attention to what everyone had expected to be a low-key, auxiliary protection force. "We're growing the capacity of the industry in a way we did not anticipate," said the official, who spoke only on the condition of anonymity. "The industry realizes they have to impose some kind of standards" on their employees.

The brutal killings of four American security contractors in Fallujah two weeks ago prompted 13 Democratic senators led by Jack Reed (R.I.), to ask the Defense Department to provide a tally of how many private armed non-Iraqi security personnel are in Iraq. In their letter, the senators said that "security in a hostile fire area is a classic military mission. Delegating this mission to private contractors raises serious questions."

"Policy is way overdue in this area," Reed said. Not only do troops need better guidance on dealing with private guards, he said, but also the CPA should want assurances that insurgents cannot infiltrate the companies as "may already be occurring in the new Iraqi police and civil defense forces."